The chalcogen elements (S, Se, and Te) are glass-formers. These elemental glasses are essentially chains that polymerize to varying lengths. Chalcogenide glasses are formed by combining chalcogen elements with Group III, IV or V elements, which are more electropositive than the chalcogens and lead to crosslinking. While some studies reveal large-scale medium-range ordering with correlation lengths up to about 50 Å, chalcogenide glasses are considered amorphous materials. Many chalcogenide glasses, for example arsenic based chalcogenide glasses such as As—S, As—Se, As—S—Se, As—Te, As—Se—Te, are semiconducting materials that transmit infrared (IR) light, rendering them useful in a variety of applications, such as IR sensors, waveguides, photonic crystals, amplifiers, lenses and as photolithography template materials. Rare earth doped chalcogenide glasses are also being investigated for highly efficient optical amplifiers and lasers.
Certain chalcogenides also have therapeutic properties and are being considered for a variety of treatments. For example, selenium, an essential trace mineral for normal metabolism, plays a protective role against cancer and can be used as an indicator of body status in cancer patients, for example in the form of a selenide, selenite (SeO32−) or selenate (SeO42−). In addition, at low concentrations, arsenic trioxide is an effective antileukaemic agent and shows promise for use against tumors that have become resistant to other anticancer drugs.
Despite the interest in chalcogenides, the ability to fabricate them on the micro and nanoscale has been limited. Accordingly, there is a need for novel systems and techniques for the nanofabrication of chalcogenides. The present invention addresses this need.